The phase singularities arising from the interference of monochromatic waves [1]} do not arrange in a completely random manner, even when the interfering waves are random [2]}.
Instead, the singularities' spatial distribution actually exhibits the hallmarks of a liquid-like system [3]}.
This behaviour of the phase singularities can be most clearly observed in the pair correlation function [3]}, [5]}, [6]}, [7]}, [8]}, [9]}, [10]}, [11]}, [12]}, [13]}, [14]}, one of the most used tools to describe the spatial arrangement of discrete systems of any kind [15]}, [16]}, [17]}.
Additionally, these singularities have a topological charge, also hinting at analogies with interacting particles, with mechanisms like same-charge repulsion [18]}, [19]} and topological screening [20]}, [21]}, [22]}, [23]}.
However, we cannot directly measure the interaction of two singularities, and comparing them to interacting particles currently does not go beyond the superficial and the use of metaphors.
